This invention relates to applicators for cosmetics, such as molded plastic applicators, and to methods of making them. In one important sense, to which detailed reference will be made herein for purposes of illustration but without limitation, the invention is particularly directed to brushes for applying mascara or the like.
Brushes of the type commonly referred to as “twisted-in-wire” brushes, constituted of fibers clamped at their midpoints in a twisted wire core, are well known and widely used in the cosmetics industry. Although acceptable for uses exemplified by the application of mascara, these brushes have certain disadvantages. They are relatively costly, and there are only a limited number of suppliers. Moreover, a conventional twisted-wire brush offers essentially only one kind of brush profile for use both to transfer mascara from a container to the face and to apply the mascara to the eyelashes. To improve application, it would be beneficial to provide mascara brushes having other structures; but the diversity of possible configurations of twisted-in-wire brushes is restricted by the requirement to trim the bristles in order to achieve desired shapes, and the difficulty of forming and positioning cutters to effect such trimming.
It has also been proposed heretofore to employ plastic brushes and combs as mascara applicators. Injection molded product suppliers are quite abundant, the cost of a molded brush can be less than that of a twisted-in-wire brush, and a wide variety of designs is theoretically possible. The production of molded plastic brushes with radiating bristles distributed around a cylindrical or like core, however, has been attended with substantial difficulties in separating the brush from the mold, owing to interference between the divergently angled brush fibers and the mold recesses provided for forming them, unless special and complex multi-part mold structures are employed.